This invention relates to cleaning apparatus in the graphic arts industry and, in particular, to a spiral brush apparatus for cleaning printing press components.
Devices employed in the printing industry become contaminated with debris such as ink and lint. This problem occurs whether the printing is on paper or fabrics. The debris also forms, to varying degrees, on all kinds of printing equipment. For example, offset printing has become the predominant printing method in the newspaper publishing industry.
Offset printing presses typically employ a blanket cylinder, that is to say, a rubber cylinder or a rubber-covered cylinder, for the purposes of receiving inked images from a printing plate. The inked images are then offset onto paper passed between the blanket cylinders or impression cylinder and blanket cylinder. Continuous printing is made possible by wrapping a print plate or a plurality of printing plates around the surface of a plate cylinder designed for rotation in contact with the blanket cylinder.
In operating blanket-to-blanket presses, a web of paper passes between two blanket cylinders mounted such that one blanket cylinder serves as an impression cylinder for the other. This results in "perfecting" which is simultaneous printing on both sides of the web of paper.
Continuous offset printing is adversely affected by dust and lint from the web of paper which tend to accumulate on the blanket cylinder(s). This dust and lint reduces the quality of the printed product. The accumulation of dust, lint or ink on a blanket cylinder thus presents a serious annoyance and necessitates undesirable down-time for cleaning. The problem is especially acute in the newspaper industry, when, in response to the rising cost of newsprint stock, less expensive grades of paper having higher lint content often are substituted for more expensive grades.
The problem of collection of debris such as ink, dust and lint on printing devices is not limited to offset printing. It occurs in press equipment in general. For example, it occurs on Anilox Rollers, Flexo Plate Cylinders and Plates, pipe rollers in newspaper presses, metal decorating press blanket cylinders, rollers and impression cylinders, Gravure press cylinders and rollers, Flexo press cylinders and rollers, and textile printing plates, blankets and rollers. The problem of cleaning printing equipment is well known as indicated by prior efforts for printing equipment cleaner devices.
In some types of printing, sheets are cut and stacked prior to printing. The sheets are prevented from sticking by application of a dusty material such as corn starch. Use of corn starch laden sheets provides another source of debris.
Previously known vacuum devices for cleaning blanket cylinders involved wet vacuum systems for removing debris. In these systems, segments of the blanket cylinder are continually immersed and cleaned with a solvent. See, for example, U.S. Pat. Nos. 3,049,997 and 3,309,993 to Grembechi et al. and 3,835,779 to Ross et al. The present invention avoids the need for solvents by employing a completely dry system for removing debris.
Additionally, the present invention employs a separate vacuum or air flow means unlike the IBM Technical Disclosure Bulletin, "Cleaner to Developer Toner Recirculation," Eide and Witte, Vol. 21, No. 5, October 1987, pp 359-360 that discloses only a slight vacuum caused by the rotation of the brush.
Lastly, this invention has arms to pivot the rotating brush cleaner between two operative positions as well as means to vary the rotation of the brush means to increase its cleaning effectiveness, unlike U.S. Pat. No. 4,134,673 to Fisher and Xerox Technical Disclosure Bulletin, "A Cleaning System," Hewitt, Vol. 3, No. 4, July/August 1978, pp 253-254.